To create a sitemap you can customize your instance without any plugin, so check this documentation which gives the steps in how to display a site map in your Confluence:
You can use Sitemap for Confluence for creating a sitemap.xml.
Using this plugin you can create sitemap.xml to your confluence site and inform search engines about pages on all spaces that are available for crawling.
It also allows to add metadata to the URLs :
Hi there, a few of us at Atlassian would love to learn about how you use "space settings" functionality in Confluence. A facelift to the space settings is long overdue and we want to start with impro...
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